For the key scene in which Wallis and Edward’s budding intimacy is revealed, Oscar-nominated costume designer Phillips dressed Edward in navy tails to match Wallis's navy gown. “It’s actually a replication of a Schiaparelli gown,” she says. Though the dress is not one that Wallis actually wore, to Phillips’s knowledge, “Wallis Simpson was a client of Elsa Schiaparelli and did wear a lot of her clothes in that particular period.”

To host a luncheon, Wallis wears a crisp sundress. “Wallis wore a lot of graphic patterns. I wanted this dress to feel as formal as it could for an outfit in the South of France, so I loved the idea of the striped pale blue and white,” Philips says.